No. 1: Dec. 31, 1967, The Ice Bowl NFL Championship, Packers vs. Cowboys, -13 degrees (-36 wind chill)
The most extreme weather during NFL games
Lake Michigan FREEZES OVER, football fans shiver in minus 19F and JFK closes for hours as extreme cold as America shivers through 'polar vortex'
No. 1: Dec. 31, 1967, The Ice Bowl NFL Championship, Packers vs. Cowboys, -13 degrees (-36 wind chill)
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Through the lens: Super Bowls, the Ice Bowl and a guarantees defined the NFL in the 1960s
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The Britannica Guide To Football, PDF, American Football Leagues